The Short Diabetes Knowledge Instrument (SDKI) was used to measure diabetes knowledge including diabetes diet, symptoms of hypoglycemia, foot care and importance of physical activity. The SDKI is a 13-item scale with scores ranging from 0 to 13 representing number of items answered correctly. The Short Diabetes Knowledge Instrument (SDKI) will be administered to all study patients at enrollment (T0) and one month follow-up (T1).

Diabetes self-care will be measured using the Summary of Diabetes Self-Care Activities (SDSCA), an 11-item questionnaire of diabetes self-management that assess the following six aspects of the diabetes regimen: general diet (2 items), specific diet (2 items), exercise (2 items), blood-glucose testing (2 items), foot care (2 items), and smoking (1 items). Item responses use the metric "days per week" except for a single item about smoking status which is yes or no. Each of the five aspects (excluding smoking) is assigned a mean score based on number of days per week. The Summary of Diabetes Self-Care Activities (SDSCA) will be administered to all study patients at enrollment (T0) and one month follow-up (T1).

The Perceived Diabetes Self-Management Scale (PDSMS) is a valid measure of diabetes self-efficacy. The PDSMS will be administered to all study participants at enrollment (T0) and one month follow-up (T1). Eight items are scored on a five-point Likert scale. The total PDSMS score can range from 8 to 40, with higher scores indicating more confidence in self-managing one's diabetes.

The Problem Areas in Diabetes Scale (PAID-5) is a valid measure of diabetes distress. The PAID-5 will be administered to all study participants at enrollment (T0) and one month follow-up (T1). Total scores on the PAID-5 can range from 0 to 20, with higher scores suggesting greater diabetes-related emotional distress.

Unique study specific items to assess participants' knowledge of measures of diabetes health status (e.g., Hemoglobin A1C) will be administered to all study participants at enrollment (T0) and one month follow-up (T1).

The Diabetes Care Profile (DCP) is a self-administered questionnaire that assesses the social and psychological factors related to diabetes and its treatment. The instrument includes sixteen scales. The Understanding Scale of the DCP contains 13 items that assesses respondents' perceived understanding of elements of diabetes self-care (e.g., diet for blood sugar control). We administered 9 of the 13 items to study participants, excluding items that referenced elements of self-management that are not covered in My Diabetes Care (e.g., pregnancy and diabetes). Respondents rate their understanding on a five-point Likert scale. The scale scores range from 1 to 5 and represents the average item score for the scale (∑ Q1-9/ Count of non-missing items). High scores indicate higher perceived understanding.

Unique study specific survey items to assess participants' attitudes toward receiving social and goal-based comparison information regarding their diabetes health status will be administered to all study participants at enrollment (T0) and one month follow-up (T1).

The Patient Activation Measure® (PAM-13) scale will be administered to all study participants at enrollment (T0) and one month follow-up (T1). The 13-item PAM® survey is a validated measure of patient activation (i.e., the knowledge, skills and confidence a person has in managing their own health and health care) and consists of 13 items. Each item uses a 4-point Likert-type scale of response options ranging from strongly disagree to strongly agree to elicit endorsement of a particular statement. PAM® survey item responses result in total raw scores ranging from 13 to 52, which we converted to the linear interval scale of patient activation scores, ranging from 0 (lowest activation) to 100 (highest activation).

Health literacy was assessed using a validated one-item screener that asked respondents to rate their confidence independently filling out medical forms on a scale ranging from 'extremely' to 'not at all' confident. Consistent with prior studies, we categorized participants noting any lack of confidence filling out medical forms as having limited health literacy.

eHealth refers to healthcare services provided electronically via the Internet. eHealth Literacy refers to the knowledge, comfort, and perceived skill at finding, evaluating, and applying electronic health information to health problems. eHealth Literacy was assessed by the eHEALS scale which contains 8 items, measured with a 5-point Likert scale with response options ranging from "strongly disagree=1" to "strongly agree=5." Total scores of the eHEALS are summed to range from 8 to 40, with higher scores representing higher self-perceived eHealth literacy.

One participant did not complete the eHEALS scale

Participants could select more than one so totals may exceed 100%.

Two participants were missing hemoglobin A1C data.

Number of participants with comorbid hyperlipidemia and/or hypertension

User experience will be assessed by study-specific survey items administered to all study participants at the end of the study period (T1). The survey items will inquire about participants' perspectives on particular features of the Patient-facing Diabetes Dashboard. Participants were asked to indicate which features, if any: (1) they found useful for managing their diabetes and which features, (2) improved their understanding of their diabetes health data, and (3) should be removed. In addition, participants indicated whether they intended to use the dashboard going forward if it remained available.

At the end of the study period (T1), a subset of study participants will be invited to complete a semi-structured interview to provide a deeper understanding of their experience using the dashboard.

participants that participated in a semi-structured interview

This is a composite outcome measure of participants' self-reported total number of diabetes dashboard visits, total duration of dashboard use, use of embedded educational links, utilization of embedded functionality to secure message healthcare team member(s), and use of an embedded link to American Diabetes Association Online Community and will be queried at the end of the study period (T1).

The Short Diabetes Knowledge Instrument (SDKI) was used to measure diabetes knowledge including diabetes diet, symptoms of hypoglycemia, foot care and importance of physical activity. The SDKI is a 13-item scale with scores ranging from 0 to 13 representing number of items answered correctly. The Short Diabetes Knowledge Instrument (SDKI) will be administered to all study patients at enrollment (T0) and one month follow-up (T1).

Missing data for one participant

Diabetes self-care will be measured using the Summary of Diabetes Self-Care Activities (SDSCA), an 11-item questionnaire of diabetes self-management that assess the following six aspects of the diabetes regimen: general diet (2 items), specific diet (2 items), exercise (2 items), blood-glucose testing (2 items), foot care (2 items), and smoking (1 items). Item responses use the metric "days per week" except for a single item about smoking status which is yes or no. Each of the five aspects (excluding smoking) is assigned a mean score based on number of days per week. The Summary of Diabetes Self-Care Activities (SDSCA) will be administered to all study patients at enrollment (T0) and one month follow-up (T1).

The overall number of participants analyzed for two blood-glucose testing items was 50, because 10 participants that do not test their blood sugar were excluded from those two items. Overall number of participants analyzed was 60 for the the other five aspects/sub-scales.

The Perceived Diabetes Self-Management Scale (PDSMS) is a valid measure of diabetes self-efficacy. The PDSMS will be administered to all study participants at enrollment (T0) and one month follow-up (T1). Eight items are scored on a five-point Likert scale. The total PDSMS score can range from 8 to 40, with higher scores indicating more confidence in self-managing one's diabetes.

One participant had missing data.

The Problem Areas in Diabetes Scale (PAID-5) is a valid measure of diabetes distress. The PAID-5 will be administered to all study participants at enrollment (T0) and one month follow-up (T1). Total scores on the PAID-5 can range from 0 to 20, with higher scores suggesting greater diabetes-related emotional distress.

Missing data for one participant.

Unique study specific items to assess participants' knowledge of measures of diabetes health status (e.g., Hemoglobin A1C) will be administered to all study participants at enrollment (T0) and one month follow-up (T1).

As noted in the outcome measure data table below, the number analyzed for some items is less than 60 due to missing data.

The Diabetes Care Profile (DCP) is a self-administered questionnaire that assesses the social and psychological factors related to diabetes and its treatment. The instrument includes sixteen scales. The Understanding Scale of the DCP contains 13 items that assesses respondents' perceived understanding of elements of diabetes self-care (e.g., diet for blood sugar control). We administered 9 of the 13 items to study participants, excluding items that referenced elements of self-management that are not covered in My Diabetes Care (e.g., pregnancy and diabetes). Respondents rate their understanding on a five-point Likert scale. The scale scores range from 1 to 5 and represents the average item score for the scale (∑ Q1-9/ Count of non-missing items). High scores indicate higher perceived understanding.

Missing data for one participant

Unique study specific survey items to assess participants' attitudes toward receiving social and goal-based comparison information regarding their diabetes health status will be administered to all study participants at enrollment (T0) and one month follow-up (T1).

The Patient Activation Measure® (PAM-13) scale will be administered to all study participants at enrollment (T0) and one month follow-up (T1). The 13-item PAM® survey is a validated measure of patient activation (i.e., the knowledge, skills and confidence a person has in managing their own health and health care) and consists of 13 items. Each item uses a 4-point Likert-type scale of response options ranging from strongly disagree to strongly agree to elicit endorsement of a particular statement. PAM® survey item responses result in total raw scores ranging from 13 to 52, which we converted to the linear interval scale of patient activation scores, ranging from 0 (lowest activation) to 100 (highest activation).

Analysis for pre-post change in Exercise sub-scale score

Analysis for pre-post change in Blood-glucose Testing sub-scale score

Analysis for pre-post change in Foot Care sub-scale score

Analysis for pre-post change in knowledge of definition of systolic blood pressure

Analysis of pre-post change in knowledge of goal range for systolic blood pressure

Analysis of pre-post change in knowledge of definition of LDL cholesterol

Analysis for pre-post change in knowledge of goal range for LDL cholesterol

Analysis of pre-post change in knowledge of definition of flu vaccine

Analysis of pre-post change in knowledge of recommended frequency of flu vaccination

Analysis of pre-post change in agreement with statement: 'Information about how my diabetes health data compares to other patients like me [social comparison information] is useful.'

Analysis of pre-post change in agreement with statement: 'Information about how my diabetes health data compares to the goals range [goal-based comparison information] is useful.